The leading edge of an aircraft wing can be fouled by various kinds of debris such as ice, snow, and mud. Accretions can form on the ground while waiting to take off, or when the aircraft flies, for example, through freezing rain and drizzle. Ice can rapidly form on wings when planes fly through clouds of cooled water droplets. The presence of the ice reduces wing aerodynamic performance.
Improvements in small airplane technology and the “hub and spoke” scheduling system used by the airline industry has resulted in many more commuter flights. Because commuter aircraft fly at lower altitudes, icing, dust, mud, and bird strike conditions are more likely to occur. Ice and other debris may accumulate on the wing close to the leading edge. Large jetliners generally use hot air from the engines to prevent ice from forming on the wings during flight, and use cleaning fluid (during washing) to remove ice and debris when on the ground. Smaller aircraft generally rely upon inflatable rubber “boots” along the wing leading edges to “pop” off accumulated ice and debris.
If ice or other debris is detected, it can be removed by the boots, heaters, or by washing. Accordingly, it is desirable to detect the presence of debris on the wing leading edge. Furthermore, other desirable features and characteristics of the techniques and technologies described herein will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.